The present invention relates to a photomechanical mouse structure, and more particularly to a mouse structure which can be easily manufactured at low cost and in which the proportion of malfunctional products is reduced.
Conventional photomechanical mouse structure is generally composed of two LEDs, two phototransistors, a qrid means, a ball member rotatably mounted in a ball hole formed on a PC board, which drives the grid means to allow or prevent the passage of the light emitted from the LED to the phototransistor. Such mouse structure is disclosed in U.S Pat. No. 4,464,652 which relates to a cursor control device including a unitary frame, having a domed housing, idler wheel block, detecting block, encoder assembly, all of which are mounted on a PC board.
U.S. Pat. No. 4,533,830 discloses an optical encoder which uses shutters for shuttering of the light source to one of two light sensors to indicate minus or plus movement. In addition, U.S. Pat. No. 4,654,525 discloses an optical rotary encoder which use four photodiodes and a detection circuit on a single substrate. U.S. Pat. No. 4,705,943 discloses a rotational optical encoder which uses a reflector on one surface and the other surface comprises two phototransistors arranged on either side of the emitting diode.
All the above conventional devices have the following shortcomings:
(1) The circuit board mounted in the lower casing of the mouse is as large as the lower casing so that the material is wasted and the cost is higher. PA0 (2) The components mounted in the casing of the mouse, such as the X, Y direction rotary shafts, slotted discs, etc. are difficult to be assembled and thus the manufacturing of the mouse is complicated. PA0 (3) The slotted discs are composed of parts made of different materials so that the assembly thereof is labor-wasting and time-wasting. PA0 (4) The idle roller is installed on a roller post and the installation thereof is difficult so that the automatic production of the mouse can be hardly performed. PA0 (5) The idle roller is mounted on the roller post and more parts thereof are required so that the manufacturing cost is relatively high.
In view of the above, the conventional mouse structures are not well designed and the cost thereof is higher. Moreover, the proportion of malfunctional products is higher.